Deep changes occured in the social stratification of developed societies during the recent years of neo-liberal capitalism. The search of new institutional forms of social and economic regulation requires a prior understanding of some fundamental features of social change. Beginning by reconstructing the social bases of the old post-war social compromises, both in Europe and United States, the article investigates the stratification effects in processes such as "Flexible specialization", "New economy", "Globalisation", "Financiarization". A social polarization trend follows the earlier social inclusion one in the yars of organized capitalism. Finally three «scenes» of social change are suggested, where we investigate new social bases for regulation: the finance-production reckoning, the regional reorganization of economy and society, the state-market new balancing.